high stiffness plastic
high stiffness plastic
(OP)
I am looking for a high stiffness, high strength, light weight plastic that can be machined to tight tolerances. It isn't really going to see high temperatures. I would like to fasten this part down with screws, but I'm not quite sure yet the best way to do that... maybe a nut, or an insert of some kind. I am not that familiar with various engineered plastics, so I thought I would see what advice people give on both the various plastics I could use, and a good way to fasten it down.
Thanks!
-Jon
Thanks!
-Jon






RE: high stiffness plastic
However, your 'requirements' are pretty vague. If you can give more detail on just how 'stiff' it needs to be, and other requirements that may help more knowledgeable folks give answers.
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?
RE: high stiffness plastic
This sounds suspiciously like a homework question. We have been inundated lately with similar real vague and clueless questions from first time posters.
Regards
Pat
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RE: high stiffness plastic
Thanks again!
-Jon
RE: high stiffness plastic
I'd still look into filled plastics for your stiffness concerns, you can get filled PEEK on McMaster-Carr.
In fact given your vague requirements looking at the materials places like McMaster(ttp://www.mcmaster.com/#plastics/=g5j281 have on the shelf might be a place to start. They give some vague material properties and it may give you a feel for cost comparisons, availability etc.
Then try to find some material properties for them - preferably in a good materials resource book but otherwise matweb or similar.
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?
RE: high stiffness plastic
PEEK is just about the most expensive plastic known to man so cost may be an issue. Glass reinforcement will certainly reduce it's cost and will upgrade some properties.
Acetal is normally the best engineering plastic (as opposed to exotic plastic) for stiffness and for thread holding in the non-reinforced state. Acetal does not respond quite so well to reinforcements as some other engineering plastics. If you want heavily reinforced, nylons and PET perform better.
No plastic will hold a thread well compared to steel and it is generally considered necessary to either use threaded metal inserts or if the load is not to high, to use special thread forms designed for plastics
Regards
Pat
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RE: high stiffness plastic
Machining reinforced phenolic is superb.
It is cheap.
Back draw: weight (starts with 1.6 g/ccm).
RE: high stiffness plastic
Coulors are VERY limited at has really poor elongation at break and poor impact. Urea or melamine gives more colour options.
It cannot be moulded as fast in normal thin sections as can thermoplastics. It moulds faster though in real thick sections
Regards
Pat
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